Apparatus of the kind, with which
powder discharge is effected by way of a lower collector, PA1 clean gas discharge is effected into an upwardly disposed clean gas channel via at least one immersion pipe which depends from the bottom of the clean gas channel and dips into a cyclone pipe into which the drawn-off gas/powder stream can be introduced axially, PA1 an annular gap between the immersion pipe and the cyclone pipe comprises a whirl generating means to set the gas/powder stream into circulating motion, belong to the state of the art (DE 32 29 756 A1, DE 41 34 701 A1, EP 0 681 871 A2).
During electrostatic coating, workpieces are transported through a powder booth to be coated with powder from spray devices. Not all of the powder actually reaches the workpiece surfaces to be coated. The excess powder which is oversprayed must be removed quickly from the powder coating booth to allow colors to be changed and for the powder to be ready for renewed use or disposal.